1. Field of Art
The invention generally relates to audio processing and more specifically to recognizing melodies in audio clips.
2. Description of the Related Art
Electronic media libraries may contain thousands or millions of video and/or audio files, making management of these libraries an extremely challenging task. A particularly challenging problem involves identifying songs within user-uploaded video or audio files. Song recognition is important for several reasons. First, song recognition allows media hosting services to detect user-uploaded media files that contain copyrighted music, and to obtain an appropriate license or remove such content. Second, song recognition allows media hosting services to generate targeted advertisements such as, for example, by providing hyperlinks directing a listener/viewer to a web site for purchasing the song or a related album. Third, song recognition allows media hosting services to automatically index media files so that users can more efficiently search for media content containing a particular song.
While user-uploaded audio content is sometimes identifiable by the file name or other metadata, these labels are often incorrect or insufficient to fully identify the audio content. An alternate approach of using humans to manually label songs in audio or video files is expensive, time consuming, and becomes increasingly unfeasible as media libraries become larger. Therefore, an automated technique for song recognition is desirable.
Traditionally, automated song recognition requires a nearly exact match between an input audio file and a labeled reference audio file. This traditional technique cannot detect matches between different recordings of the same song (e.g., matching a cover song to the original), when the song is transposed to a different key, or when different instrumentation is used.